Novel antimicrobic compositions containing a nitroalkyl n-phenylcarbamate

ABSTRACT

NOVEL COMPOSITIONS AND METHOD FOR KILLING BACTERIA AND FUNGI HAVING AS THE ACTIVE INGREDIENT A NITRO ALKYL-NPHENYL CARBAMATE AND TO NOVEL BROMO-NITROALKYL-NPHENYLCARBAMATES.

United States Patent Office 3,592,928 Patented July 13, 1971 Int. Cl. A6111 9/20 US. Cl. 424-204 16 Claims ABSTRACT OF THE DISCLOSURE Novel compositions and method for killing bacteria and fungi having as the active ingredient a nitro alkyl-N- phenyl carbamate and to novel bromo-nitroalkyl-N- phenylcarbamates.

STATE OF THE ART Many organic nitro compounds are known to possess antibacterial properties and examples of such compounds are aromatic nitro compounds, nitro-substituted pyridine derivatives, nitrofurfural derivatives, many aliphatic nitro, di-nitro and polynitro compounds. Of particular interest as preservatives have been aliphatic nitro alcohols and brominated derivatives thereof due to their broad spectrum of activity. These compounds, however, have the disadvantage of showing signs of decomposition after storage under atmospheric conditions for a short time and they generally have only a low degree of activity which is disadvantageous for impregnating wood and textiles for instance.

Known fungicides include nitro alcohols and esters of nitro alcohols with monoand polybasic carboxylic acids but these products are only effective against fungi and not against bacteria. Therefore, their limited spectrum is too restricted for general use as antimicrobic agents. Up to now, there has been no reliable known connection between chemical structure and antimicrobic activity. For example, urbanski in Nitro Compounds, Warsaw, 1964, page 449 et seq., discloses that ethyl 4-chloro-4,4- dinitro butyrate and 2-bromo-Z-nitro-propanediol-1(1,3) have a high activity against micro-organisms while ethyl 4-bromo-4,4-dinitro butyrate and 2-chloro-2-nitro-propanediol-(l,3) are substantially devoid of any such activity.

OBJECTS OF THE INVENTION It is an object of the invention to provide novel bromonitroalkyl-N-phenylcarbamates.

It is an additional object of the invention to provide novel anti microbic compositions having a nitro-alkyl-N- phenylcarbamate as the active ingredient.

It is a further object of the invention to provide synergistic anti mircrobic compositions.

It is another object of the invention to provide improved methods for killing bacteria and fungi.

These and other objects and advantages of the invention will become obvious from the following detailed description.

THE INVENTION The novel anti microbic compositions of the invention aer comprised of an effective amount of a nitro-alkyl-N- phenylcarbamates of the formula.

Yu A I wherein Y is selected from the group consisting of chlorme an nitro, n is a whole number from 0 to 2, A is a carbamic acid ester group of the formula wherein R is selected from the group consisting of hydrogen and methyl, X is selected from the group consisting of hydrogen and bromine and B is selected from the group consisting of hydrogen, methyl, ethyl and a phenylcarbamic acid group of the formula wherein Y, n and R have the above definitions and a major amount of an inert carrier.

All the nitroalkyl-N-phenylcarbamates of Formula I possess bactericidal and fungicidal activity and are useful in am'timicrobic compositions. Particularly preferred are the compounds of Formula I wherein X is bromine which are novel compounds as they have a particularly high degree of activity and are effective microbicides at low concentrations. The compounds of Formula I have the advantages of strong fungicidal activity, excellent activity against gram-positive and gram-negative bacteria, no tendency to decompose and high degree of activity for impregnation.

Examples of specific nitroalkyl-N-phenylcarbamates of Formula I are:

2-nitroethyl-N-phenylcarbamate 2-nitroethyl-N- 3-chlorphenyl) -carbamate Z-nitroethyl-N- 3 ,4-dichlorophenyl) -carbamate Z-nitroethyl-N- (4-nitrophenyl -carbamate l-methyl-Z-nitroethyl-N- 3 ,4-dichlorophenyl) -carb amate 2-nitropropyl-N-phenylcarbamate Z-nitropropyl-N- 3-chlorophenyl) -carbamate 2-nitrobutyl-N-phenylcarbamate 1-methyl-2-nitropropyl-Nphenylcarbamate l-methyl-Z-nitrobutyl-N- (4-nitrophenyl -carbamate 2-bromo-2-nitroethyl-N- 3 -chlorophenyl) -carbam ate l-methyl-2-bromo-2-nitroethyl-N-phenylcarbamate 2-bromo-2-nitropropyl-N- 3-chloropheny1) -carbamate 2-bromo-2-nitrobutyl-N-phenylcarbamate 2-bromo-2-nitr0butyl-N- 3,4-dichlorophenyl) -carbamate 1-methy1-2-bromo-2-nitropropyl-N- (4-nitrophenyl) carbamate l-methyl-2-bromo-2-nitrobutyl-N-phenylcarbamate 2-nitropropanediol- 1,3 bis-N-phenylcarbamate Z-nitropropanediol- 1,3 -bis-N- 3,4-dichlorophenyl) carbamate l-methyl-2-nitropropanediol- 1,3 -bis-N- 3 -chlorophenyl) -carbamate 1, 3 -dimethyl-2-nitropropanedioll 3 -bis-N- (4- nitrophenyl) -carbamate 2-bron1o-2-nitropropanediol-( 1,3 -bis-N-phenylcarbamate 2-bromo-2-nitropropanediol-(1,3 )-bis-N- 3-chlorophenyl -carb amate 2-bromo-2-nitropropanedio1-( 1,3 -bis-N-(3 ,4-

dichlorophenyl) -carbamate 2-bromo-2-nitropropanediol- 1,3 )-bis-N- (4-nitrophenyl) -carbamate 1-methyl-2-bromo-2-nitropropanedioll, 3 -bis-N- (3-chlorophenyl) -carbamate 1,3-dimethyl-2-bromo-nitropropanediol- 1,3 -bis-N- (3 ,4-di-chlorophenyl) -carbamate. The antimicrobic compositions of the invention may be in the form of liquid, pasty or solid preparations such as aqueous suspensions, emulsions, solutions in organic solvents, oils, ointments, creams, pencils, powders, soaps, toothpastes and mouthwashes which may be used as cleansing agents, general and special skin treatment agents and other cosmetic compositions. The compositions usually contain 0.05 to 5% by weight, preferably 0.1 to 1% by weight of the said nitro-a1kyl-N-phenylcarbamate.

In a modification of the antimicrobic compositions of the invention, synergistic compositions are comprised of an effective amount of a complexing agent having a calcium carbonate binding capacity greater than 230 mg. per gm. of complexing agent in the Hampshire test and at least one nitro-alkyl-N-phenylcarbamate of Formula I in a weight ratio of carbamate to complexing agent of 1:1000 to 50: 1, depending upon the specific components.

The complexing agent in the compositions of the invention having a calcium carbonate binding capacity of more than 230 mg. in the Hampshire test may belong to varied classes of compounds such as polycarboxylic acids, hydroxy carboxylic acid, aminocarboxylic acids, phosphonic acids and polyphosphonic acids and their alkali metal salts. The Hampshire method for determining calcium carbonate binding capacity is described in the publication of the Hampshire Chemical Corporation of June 1960, Hampshire NTA Technical Bulletin, Appendix, p. A2. In the method, exactly 2 gm. of a powdery complexing agent are dissolved in 50 cc. of distilled water after which the solution is neutralized and admixed with 10 ml. of a 2% sodium carbonate solution. The pH is adjusted to 11- 12 and the solution is diluted to 100 ml. Then the solution is titrated with a calcium acetate solution containing 44.1 gm. of calcium acetate monohydrate per liter until a distinct and lasting turbidity occurs. The calcium carbonate-binding capacity is determined according to the formula:

cc. calcium acetate solution 25 weight portion of complexing agent =mg. calcium carbonate bound per gm. of

oomplexing agent In the following examples are described several preferred embodiments to illustrate the invention. However, it should be understood that the invention is not intended to be limited to the specific embodiment.

EXAMPLE I Using the same procedure, the compounds of Table A were prepared from the appropriate alcohol and phenylisocyanate.

specific amount of the substance solutions of suitable concentrations with specific amounts of liquid bouillon or beer wort-agars, in sterile petri-dishes. The amounts, measured with a pipette, of the substance solutions were a maximum of 0.1 to 1 ml. and the total volume in the petri-dishes after admixing with the culture media amounted to 10 ml. After solidification of the culture media, its surface was inoculated with the test germ suspension in bouillon or wort, which contained about 10 germs per ml. The incubation took place at 37 C. or at 30 C. in the incubator, and lasted 8 days when bacteria or Candida albicans were employed. When epidermophyton Kaufmann-Wolf were used, it lasted 21 days. The duration of incubation of 21 days for epidermophyton Kaufmann-Wolf was chosen to conform to the above standard test, because in the evaluation of disinfectants against fungi of the epithelium a substance is considered as suitable when the growth of the fungi after predetermined duration of action is delayed by at least 21 days. Therefore, it was ascertained which of the substance concentrations worked into the culture media was just about capable to arrest the growth of the test germs completely. This value thus ascertained was indicated as threshold concentration. The tests were carried out in the following concentration intervals:

10,000, 5,000, 2,500, 1,000, 750, 500, 250, 100, 50, 25, 10, 5, 2.5, 1, 0.5, 0.25 and 0.1 p.p.m.

TABLE I Test germs Epiderm- Pseudomophyton C0 ncentra- Staphylococ- Escherichia onus aeru- Candida Kaufmann- Agent t1on1np.p.m. cus aureus coli ginosa albicam Wolf Test germs Epiderm- Pseudomophyton Concentra- Staphylocac- Escherichia onus aeru- Candida Kaufmann- Agent tioninp.p.m. cue aureus coli ginosa albica'ns f gg +3 D 10 5 2.5 1 0.5 +1 500 250 100 E 22 i 1: I. 500 250 100 50 F if; 1: :r 5 2.5 1 0.5 500 250 100 22 i i G 10 ":31:

N oTE.-In the table: =No growth, Growth.

7 EXAMPLE II The fungicidal activity of 2-nitropropyl-N-phenyl-carbamate (B) and Z-nitropropyl-N-(3-chl0rophenyl)-carbamate (D in the gaseous phase was shown by the following procedure. The compounds were dissolved in acetone and then applied to round filter paper, after which the acetone was evaporated off at 20 C. The said filter paper was placed in the cover of a petri-dish (90 mm. diameter) and the lower part was filled with agar which was surface inoculated with the germs of Table II.

An intermediate space of about 5 to 6 mm. in width existed between the filter paper and the surface of the nutrient medium. The dishes were then incubated at 30 C. for up to 4 weeks and evaluated. The numerical values given in Table II relate to the amounts of active substance in mg. required on the filter paper which was just sufiicient for a complete inhibition growth of the germs.

ployed. When Epidermophyton Kaufmann-Wolf was used, it lasted 21 days. The duration of incubation of 21 days for Epidermophyton Kaufmann-Wolf was chosen to conform to the above standard test, because in the evaluation of disinfectants against fungi of the epithelium a substance is considered as suitable when the growth of the fungi after predetermined duration of action is delayed by at least 21 days. Therefore, it was ascertained which of the substance concentrations worked into the culture media was just about capable to arrest the growth of the test germs completely. The tests were carried out in the various concentrations of carbamates and with 1000 p.p.m. of the complexing agent. The complexing agents alone had no inhibiting activity on the growth of the micro-organisms. The results of the tests are shown in Tables IV to VII.

In Tables IV to VII, the designations for the column headings are as follows:

TABLE II Suppression of the growth of some fungi from the gaseous phase Clado- Tricho- Epider- Triphy- Asp. Asp. Asp. spcrium derma Peneamemophyton Agent m'uer tamarii flavua sp. viride runense ton rubrum EXAMPLE III 1=Antimicrobic agent Examples of complexing agents having a calcium carbonate binding capacity of more than 230 mg. per gm. of

complexing agent are shown in Table III. 30

TABLE III Complexing agent Mg. 0! calcium carbonate bound by 1 gm.

of agent;

Kl l-hydroxyhexane-l,l-diphosphonic acid.

K2 a-Aminoethane-a,a-dipl1osphonic acid.

oz-Aminobenzyl-a,a-diphosphonlc acid Aminotrimethylenephosphonic acid (Dequest 2000) Ethylenediamine tetrarnethylenephosphonic acid K-3 Aminodimethylenephosphonic acid N -acetic acid..

Iminodiacetic acid-N-methylenephosphonic acid- Hydroxyethanediphosphonic acid Phosphonic acetic acid Citric acid K4..- Diethylenetriaminopenta acetic acid (DTPA) K-5 1,2-eyclohexanediamine-tctra acetic acid (ODTA) K6 Ethylenediamino-tetra acetic acid (EDTA) K-7. Nitrilotriacetic acid (NTA) K8 COOH (IJOOH CHNHCH CHz-NHCH Chel DP O H OH The threshold concentrations of the nitroalkyl-N-phen- I ylcarbamates of Table A and combinations thereof with complexing agents of Table III were determined by the so-called plate test. This variation of the dilution test for chemical disinfectants set up by Deutsche Gesellschaft fiir Hygene und Mikrobiologie has the advantage of using a solid culture media instead of a liquid culture media. Solid culture media have the advantage of being able to easily discern the effectiveness, particularly for fungicides.

The desired test concentration were prepared by mixing specific amounts of the substance solutions of suitable concentrations with specific amounts of liquid bouillon or beer-Wort agars, in sterile petri-dishes. The amounts, measured with a pipette, of the substance solutions were a maximum of 0.1 to 1 ml. and the total volume in the petridishes after admixing with the culture media amounts to 10 ml.

After solidification of the culture media, its surface was inoculated with the test germ suspension in bouillon or wort, which contained about 10 germs per ml. The incubation took place at 37 C. or at 30 C. in the incubator, and lasted 8 days when bacteria Candida albicans were em- 4=Inhibiting concentration of the antimicrobial substance with simultaneous insertion of 1000 p.p.m. of complex forming compound TABLE IV.Staph1 lococcus aureus TABLE V.Escherichia coli 100 K-7 25 4 100 K-4 10 10 250 K-1 50 5 250 K-7 50 5 250 K-4 100 2. 5 250 11-8 100 2. 5 100 K-1 10 10 100 K-4 25 4 100 K-7 25 4 100 K6 25 4 100 K-4 10 10 100 K-8 25 4 TABLE VI.-andida albz'cans 250 K-8 50 5 500 R4 100 5 5 K4 1 5 25 K-4 5 5 50 K-8 5 TABLE VII.-Epidermophyton Kauimann-Wolf 10 K-3 1 10 1 K-5 0. 4 2. 5 K-5 1 2. 5 1 K-3 0. 1 10 2. 5 K-6 0. 25 10 10 K-7 2. 5 4

Tables IV to VII clearly demonstrate the synergisitc activity of the compositions of the invention as compared to the phenylcarbamate alone or the complexing agent alone. The complexing agents listed in Table VHI have a calcium carbonate binding capacity below 230 mg. per gm. in the Hampshire test and when used in combination with the nitro alcohols in the test there was no increase in (A) Antimicrobial solution: Parts by Weight 2 bromo 2 nitrobutyl N (3,4-dichlorophenyl) carbamate 3.0 Spirit dil. ad 50 (B) Antimicrobial salves:

(1) 2 bromo 2 nitroethyl N-(3-chlorophenyl)-carbamate 3.0 Vaseline alba ad 100 (2) 2 bromo 2 nitropropanediol (1,3)- bis N (3,4 dichlorophenyl) carbamate 3.0 Ungetum alcohol, lanae ad 100 (3) 2 bromo 2 nitropropyl N-(4-nitrophenyD-carbamate 3.0 Polyethylenglycol 300 and polyethyleneglycol 1500 1:1 ad 100 (4) 2-bromo 2 nitropropandiol (1,3)-

bis-N-(3-chlorophenyl)-carbamate 3.0 Oleic acid decyl ester 16.0 Colloid dispersive mixture of 90 parts of C -C -alcohol and 10 parts of sodium fatty alcohol sulfate of 16 :to 18 carbon atoms 24.0

Water 57.0

10 (C) Antimicrobial powder: Parts by weight 2-bromo-2-nitrobutyl-N-(3,4 dichlorophenyl)- carbamate Talcum powder ad 100 (D) Day cream and lotion:

l-methyl 2 bromo 2 nitropropyl-N-(3- Sodium lauryl ether sulfate (27-28% WAS) 40.

Diethanolamide of coconut fatty acid 6.0 Water 53.0 (F) Emulsion shampoo:

2-bromo 2 nitropropanediol-(l,3)-bis-N- phenyl-carbamate 1.0

Sodium lauryl sulfate WAS) l0.

Diethanolamide of coconut fatty acid 3.0 Ethyleneglycol stearate 2.0 Sodium chloride 1.0 Water 83.0 (G) Shampoo with egg yolk:

2-bromo 2 nitro-propanediol-(1,3)-bis-N-(4 nitrophenyl) -carbamate 1.0

Fatty alcohol sulfate of 16 to 18 carbon atoms (40% WAS) 44.0

Technical liquid egg yolk 2.0 Sodium chloride 0.3 Water 52.7 (H) Bubble bath:

2 bromo 2 nitrobutyl-N-(3,4 dichlorophenyl)-carbamate l 0 Diethanolamide of coconut fatty acid 5.0

Water 25.0 (I) Disinfectant hand wash paste:

Sodium lauryl sulfate 45 Monoethanolamide of coconut fatty acid 3 Finely ground pumice 41 2 bromo 2 nitrobutyl-N(3,4 dichlorophenyl)-carbamate 1 Disodium salt of nitrilotriacetic acid 10 (J Antimicrobial scouring agent:

Dodecylbenzene sulfonate (WAS 30%) 20 Sodium sulfate 2 Disodium salt of nitrilotriacetic acid l0 2-bromo-2-nitrobutyl-N-phenyl-carbamate 1 Finely ground pumice 5 Finely ground quartz powder 62 Perfume (K) Antimicrobial fine detergents:

Dodecylbenzene sulfonate 24 Toluenesulfonate 1.5 Sodium coconut fatty alcohol sulfate 5 Sodium sulfate 25 Sodium carboxymethyl cellulose 1 2-bromo 2 nitropropanediol-(1,3)-N-(3,4-

dichlorophenyl)-carbamate 1 Disodium salt of nitrilotriacetic acid 30 Water 12.5 (L) Disinfectants for equipment and instruments:

u-Aminoethane-a,a-diphosphonic acid 99 2 bromo 2 nitrobutyl-N-(3,4 dichlorophenyl)-carbamate 1 (M) Clear antiseptic shampoo:

Sodium lauryl ether sulfate (2728% WAS) 40 Diethanolamide of coconut fatty acid 6 Parts by weight 2-bromo-2-nitroethyl-N-( 3-chlorophenyl) 1 Sodium salt of ethylenediaminetetraacetic acid 3 Water 50 (N) Bubble bath with antimicrobial effect:

Sodium lauryl ether sulfate (27-28% WAS) 65 Diethanolamide of coconut fatty acid 5 2-bromo 2 nitropropanediol-(1,3)-bis-N-(3- chlorophenyl -carbamate 1 Sodium salt of ethylenediaminetetraacetic acid 3 Water 26 The advantage obtained by the invention resides in the fact that the compositions guarantee full protection both towards gram positive and gram negative bacteria and towards fungi due to the strong effect of its active substance. This good effect of the agent per se can be still greatly increased through a combination with complex formers which in the Hampshire test according to the calcium carbonate method possess a calcium carbonate binding capability greater than 230 g. per 1 g. of complex former, so that the concentration of disinfectant substance in the agent can be decreased without diminishing its germ killing effect. This is particularly important in those cases where higher concentrations of the disinfectant substance could cause detrimental or undesired side effects to occur as in the case of body washing agents.

Various modifications of the compositions and method of the invention may be made without departing from the spirit or scope thereof, and it should be understood that the invention is to be limited only as defined in the appended claims.

We claim:

1. An antifungal and antibacterial composition comprising 0.05 to 5% by weight of a nitro-alkyl-N-phenylcarbamate of the formula Yu A wherein Y is selected from the group consisting of chlorine and nitro, n is a whole number from 0 to 2, A is a carbamic acid ester group of the formula lOl /NO2 NHCO-ICH(|3\ R B X wherein R is selected from the group consisting of hydrogen and methyl, X is selected from the group consisting of hydrogen and bromine and B is selected from the group consisting of hydrogen, methyl, ethyl and a phenylcarbamic acid group of the formula Yn R wherein Y, n and R have the above definitions and the balance a major amount of an inert carrier.

2. The composition of claim 1, wherein X is bromine.

3. The composition of claim 1, wherein the carbamate is 2-bromo-2-nitroethyl-N- 3-chlorophenyl -carbamate.

4. The composition of claim 1, wherein the carbamate is 2-bromo-2-nitropropyl-N-(4-nitrophenyl)-carbamate.

5. The composition of claim 1, wherein the carbamate is 2-bromo-2-nitrobutyl-N-phenyl-carbamate.

6. The composition of claim 1, wherein the carbamate is 2-bromo-2-nitrobutyl-N-(3,4 dichlorophenyl)-carbamate.

7. The composition of claim 1, wherein the carbamate is l-methyl 2 bromo 2 nitropropyl-(3-chlorophenyl)carbamate.

8. The composition of claim 1, wherein the carbamate is 2 bromo 2 nitropropanediol (1,3) bis-N-phenylcarbamate.

9. The composition of claim 1, wherein the carbamate is 2 bromo 2 nitropropanediol (1,3) bis-N-(3- chlorophenyl)carbamate.

10. The componition of claim 1, wherein the carbamate is 2 bromo 2 nitropropanediol (1,3) bis-N- (3,4-dichlorophenyl)carbamate.

11. The composition of claim 1, wherein the carbamate is 2 bromo 2 nitropropanediol (1,3) bis-N- (4-nitrophenyl)carbamate.

12. The composition of claim 1 which also contains a complex former which has a calcium carbonate binding capacity greater than 230 mg. per gm. of complex former in a weight ratio of carbamate to complex former of 121000 to 50:1, said binding capacity being calculated as 25 times the number of cc. of solution of 44.1 gm. of calcium acetate monohydrate per liter to titrate to turbidity a solution of 2 mg. of complex former and 10 cc. of a 2% sodium carbonate solution diluted to cc. divided by the weight portion of complex former.

13. The composition of claim 12, wherein the complex former is selected from the group consisting of polycarboxylic acids, hydroxy carboxylic acid, aminocarboxylic acids, phosphonic acids, polyphosphonic acids and their alkali metal salts.

14. A method of combating fungi and bacteria which comprises contacting bacteria and fungi with an amount of a nitroalkyl-N-phenylcarbamate of the formula Yu A wherein Y is selected from the group consisting of chlorine and nitro, n is a whole number from 0 to 2, A is a carbamic acid ester group of the formula wherein R is selected from the group consisting of hydrogen and methyl, X is selected from the group consisting of hydrogen and bromine and B is selected from the group consisting of hydrogen, methyl, ethyl and a phenylcarbamic acid group of the formula wherein Y, n and R have the above definitions sufficient to kill the fungi and bacteria.

15. The method of claim 14 wherein there is also present a complex former which has a calcium carbonate binding capcity greater than 230 mg. per gm. of complex former in a weight ratio of carbamate to complex former of 1:1000 to 50:1, said binding capacity being calculated as 25 times the number of cc. of solution of 44.1 gm. of calcium acetate monohydrate per liter to titrate to turbidity a solution of 2 gm. of complex former and 10 cc. of a 2% sodium carbonate solution diluted to 100 cc. divided by the weight portion of complex former.

16. The method of claim 14, wherein X is bromine.

References Cited UNITED STATES PATENTS 9/1960 Pullen et al. 424300 5/1966 Harrison 260-471-C US. Cl. X.R. 4242l1, 223, 300 

